Impact of COVID-19 pandemic on the incidence and severity of myasthenia gravis in Korea: using National Health Insurance Service database.

Background: This study investigated the impact of COVID-19 pandemic on the incidence and severity of myasthenia gravis (MG) using the National Health Insurance Service (NHIS) database in Korea. Methods: We analyzed data from patients with MG in the NHIS registry from 2015 to 2021. MG was defined as (1) patients aged ≥18 years with the G70.0 code, and (2) patients who visited tertiary hospitals regarldless of department in Korea (outpatient clinics at least twice or hospitalization at least once), and (3) patients who were prescribed pyridostigmine as MG medications at least once. We designated pre-COVID-19 as 2019 and post-COVID-19 as 2021 and analyzed the MG incidence and prevalence in 2019 and 2021. We compared the clinical data of patients with MG between the two years. MG exacerbation was defined as the administration of intravenous immunoglobulin or plasma exchange. Analysis of COVID-19 cases was conducted using an integrated database from the Korea Disease Control and Prevention Agency and NHIS. Patients with MG were divided into two groups according to COVID-19 status to compare their clinical characteristics. Results: A total of 6,888 and 7,439 MG cases were identified in 2019 and 2021, respectively. The standardized incidence was 1.56/100,000 in 2019, decreasing to 1.21/100,000 in 2021. Although the frequency of MG exacerbations was higher in 2019, there were no differences in the number and duration of hospitalizations, duration of ICU stays, hostalization expense, and mortality between 2019 and 2021. Patients with MG and COVID-19 had a higher frequency of MG exacerbations than patients without COVID-19, but there were no differences in the number and duration of hospitalizations, hospitalization expense, and mortality. Conclusion: This study was the first nationwide population-based epidemiological study of MG during COVID-19 pandemic in Korea. The incidence of MG decreased during COVID-19 pandemic, and the severity of MG was not affected by COVID-19.

Body mass index is associated with clinical outcomes in idiopathic pulmonary fibrosis.

Association between body mass index (BMI) and prognosis in patients with idiopathic pulmonary fibrosis (IPF) remains uncertain. We investigated the association between BMI and clinical outcomes in patients with IPF using national health claims data. The study included 11,826 patients with IPF and rare incurable disease exemption codes (mean age: 68.9 years, male: 73.8%) and available BMI data who visited medical institutions between January 2002 and December 2018. Multivariable Cox proportional hazard models were used to evaluate the association of BMI with all-cause mortality and hospitalization. Based on BMI, 3.1%, 32.8%, 27.8%, and 36.4% were classified as underweight, normal, overweight, and obese, respectively. Multivariable analysis showed independent associations of overweight (hazard ratio [HR] 0.856, 95% confidence interval [CI] 0.801-0.916) and underweight (HR 1.538, 95% CI 1.347-1.757) with mortality in patients with IPF. Similarly, overweight (HR 0.887, 95% CI 0.834-0.943) and underweight (HR 1.265, 95% CI 1.104-1.449) were also associated with hospitalization in patients with IPF in the multivariable analysis. Spline HR curve analysis adjusted for all covariates revealed a non-linear relationship between BMI and mortality in patients with IPF. Our data suggest that BMI is associated with clinical outcomes in patients with IPF.

Time interval between surgery and adjuvant chemotherapy in patients with gastric cancer after gastrectomy: a population-based cohort study using a nationwide claim database.

Background: Adjuvant chemotherapy can reduce recurrence rates by eradicating microscopic metastases which may persist after curative resection. However, the optimal time interval (TI) between the surgery and chemotherapy remains controversial. Objectives: This study investigated the optimal TI between surgery and chemotherapy. Design: A population-based cohort study using a nationwide claims database. Methods: The data were obtained from the Korean National Health Insurance Service (NHIS) of Korea. We included patients who underwent gastrectomy between 2013 and 2018. To determine the optimal cutoff point of TI, a restricted cubic spline Cox regression model was established, and categorized the population into three groups based on TI: the early (⩽20 days), the late (⩾35 days), and the reference group (21-34 days), and with the reference group having the lowest mortality and recurrence. Propensity score matching was performed for each group. The primary outcomes were disease-free survival (DFS) and overall survival (OS). Results: After excluding ineligible participants, 6602 patients were included. The median DFS and OS did not differ significantly between the early and reference groups (p = 0.7258 and p = 0.6056, respectively). In comparison between the late and reference groups, it was significantly lower in the late group (p = 0.0079). Five-year DFS rates were 77.6% and 81.3% in the late and reference groups, respectively. The late group showed worse OS than the reference group (p = 0.0336). Five-year OS rates were 82.1% and 85.0% in the late and reference groups, respectively. In the multivariable analysis, DFS in the late group retained inferiority [adjusted hazard ratio (aHR): 1.138, 95% confidence interval (CI): 1.003-1.292, p = 0.045]. OS showed a worse trend without significance compared to the reference group (aHR: 1.138, 95% CI: 0.984-1.317, p = 0.0805). Conclusion: Adjuvant chemotherapy after gastrectomy in patients with gastric cancer should be initiated within 5 weeks of surgery. A delay of more than 5 weeks may have a detrimental effect on the subsequent disease course.

When is the best time to start adjuvant chemotherapy after stomach cancer surgery? After a patient undergoes surgery for stomach cancer, if it is stage 2 or 3, they will receive chemotherapy for a certain period of time to reduce the possibility of recurrence. However, physicians are not clear about when it is best to start chemotherapy after surgery. The study aimed to find out the best time interval between surgery and chemotherapy for patients with gastric cancer. We used data from a nationwide claims database in Korea and included patients who underwent gastrectomy between 2013 and 2018. The population has categorized the population into three groups based on the time interval: early (⩽ 20 days), late (⩾ 35 days), and reference group (21-34 days). We made statistical adjustments to minimize heterogeneity for each patient during the analysis. After excluding ineligible participants, 6,602 patients were included in the study. As a result of the analysis, it was observed that the possibility of recurrence was significantly increased for patients in the late group compared to the reference group. The probability of survival without recurrence for 5 years (5-year disease-free survival) was 77.6% and 81.3%, respectively. Meanwhile, there was no difference in the recurrence rate between the early group and the reference group. Since recurrence of cancer can ultimately lead to death, we examined the possibility for all-cause mortality and could observe a similar pattern of association with recurrence probability. The late group had a lower survival rate than the reference group (82.1% vs. 85.0%, respectively). However, there was no statistically significant difference between these two numbers. Even in a statistical model adjusting other clinical factors, the recurrence rate in the late group was still found to be significantly high compared to the reference group. In conclusion. the results showed that adjuvant chemotherapy after gastrectomy in patients with gastric cancer should be initiated within five weeks of surgery. A delay of more than five weeks may have a detrimental effect on the patient's health.

Smoking status and clinical outcome in idiopathic pulmonary fibrosis: a nationwide study.

BACKGROUND: Smoking status has been linked to the development of idiopathic pulmonary fibrosis (IPF). However, the effect of smoking on the prognosis of patients with IPF is unclear. We aimed to investigate the association between smoking status and all-cause mortality or hospitalisation by using national health claims data. METHODS: IPF cases were defined as people who visited medical institutions between January 2002 and December 2018 with IPF and rare incurable disease exempted calculation codes from the National Health Insurance Database. Total 10,182 patients with available data on smoking status were included in this study. Ever-smoking status was assigned to individuals with a history of smoking ≥ 6 pack-years. The multivariable Cox proportional hazard model was used to evaluate the association between smoking status and prognosis. RESULTS: In the entire cohort, the mean age was 69.4 years, 73.9% were males, and 45.2% were ever smokers (current smokers: 14.2%; former smokers: 31.0%). Current smokers (hazard ratio [HR]: 0.709; 95% confidence interval [CI]: 0.643-0.782) and former smokers (HR: 0.926; 95% CI: 0.862-0.996) were independently associated with all-cause mortality compared with non-smokers. Current smokers (HR: 0.884; 95% CI: 0.827-0.945) and former smokers (HR: 0.909; 95% CI: 0.862-0.959) were also associated with a reduced risk of all-cause hospitalisation compared with non-smokers. A non-linear association between smoking amount and prognosis was found in a spline HR curve and showed increasing risk below 6 pack-years. CONCLUSION: Ever-smoking status may be associated with favourable clinical outcomes in patients with IPF.

Association of Antiarrhythmic Drug Therapy With Syncope and Pacemaker Implantation in Patients With Atrial Fibrillation.

BACKGROUND: Early rhythm control therapy mainly with antiarrhythmic drugs (AADs) for new-onset atrial fibrillation (AF) reduces major adverse cardiovascular events. However, negative dromotropic effects of AADs via ion channel blocking may cause bradyarrhythmias. OBJECTIVES: This study aimed to evaluate the association between AAD use and the risk of pacemaker implantation or syncope in patients with new-onset AF receiving early rhythm control therapy with AADs. METHODS: This study was based on data from the Korean National Health Insurance Service system. We screened all new-onset AF diagnoses that occurred from 2013 to 2019 and identified patients who were prescribed AADs within 1 year of AF diagnosis. The risk of pacemaker implantation or syncope was compared between AAD users and nonusers. RESULTS: A total of 770,977 new-onset AF cases were identified and 142,141 patients were prescribed AADs. After multivariate adjustment, use of AADs was associated with 3.5-, 2.0-, and 5.0-fold increased risk of pacemaker implantation or syncope, syncope, and pacemaker implantation, respectively. Propensity score-matched analysis revealed similar results, demonstrating a significant association between AAD use and the risk of pacemaker implantation or syncope. This association was consistent across various subgroups. Women were more susceptible to adverse effects of AADs than men. CONCLUSIONS: This study showed an association between AADs and risk of pacemaker implantation or syncope, a consistent finding across various subgroups. Precise evaluation of such risk should be undertaken before prescription of AADs.

Percutaneous coronary intervention versus medical therapy in stable angina: a matched cohort study.

OBJECTIVE: It is uncertain whether percutaneous coronary intervention (PCI) in addition to optimal medical therapy (OMT) can reduce adverse clinical events in the long term as compared with OMT alone in patients with pure stable angina. METHODS: We enrolled patients from 2006 to 2010 using the Korean national insurance data. 58 742 patients with pure stable angina with no history of myocardial infarction (MI) nor PCI were candidate, and finally, 5673 patients in the PCI plus OMT group and 5673 in the OMT alone group were selected with 1:1 propensity matching. They were followed up for 9.3 years. RESULTS: Primary endpoint, a composite of MI, stroke and cardiac death rate was significantly higher in the PCI group than in the OMT group, 13.5/1000 vs 11.5/1000 person-year with HR of 1.18 (95% CI 1.06 to 1.32, p=0.003). Individual event rate of MI and cardiac death rate was higher in the PCI group than in the OMT group at 9.3 years, 2.9 vs 2.1 (HR 1.38, 95% CI 1.09 to 1.7, p=0.009) and 4.8 vs 3.4/1000 person-year (HR 1.40, 95% CI 1.16 to 1.69, p=0.001), respectively. Revascularisation and total death occurred more in the PCI group as compared with the OMT group, 30.3 vs 8.2 (HR 3.64, 95% CI 3.27 to 4.05, p<0.001) and 13.5 vs 10.6/1000 person-year (HR 1.23, 95% CI 1.12 to 1.40, p<0.001), respectively. In subgroup analysis, the same trend of more event in the PCI group was detected. CONCLUSIONS: PCI plus OMT was associated with higher rate of primary endpoint of MI, stroke, cardiac death as compared with OMT alone in patients with pure stable angina at 9.3-year follow-up in large population.

The Long-Term Impact of 5-alpha Reductase Inhibitors on the Development of Bladder Cancer and the Need for Radical Cystectomy: A Nationwide Observational Study.

PURPOSE: To investigate the long-term effects of taking 5-alpha reductase inhibitors (5ARIs) on the development of bladder cancer (BC) and the implementation of radical cystectomy (RC), a standard procedure for advanced BC. MATERIALS AND METHODS: From the National Health Insurance Sharing Service database, males aged over 40 years who underwent serum prostate-specific antigen testing from 2006 through 2017 were identified, which is required for the prescription of 5ARIs. The association between the administration duration of 5ARIs and the practice for BC was analyzed. RESULTS: Of the 3,843,968 subjects, 1,514,713 (39.4%) took 5ARIs for an average of 1.53 years, remaining 2,329,255 (60.6%) as non-5ARI counterparts. The incidence of BC was higher in the non-5ARI than in the 5ARI group (1.25% vs. 0.87%, p<0.001), as was the implementation rate of RC (11.1% vs. 10.4%, p=0.037). In a multivariate analysis, the non-5ARI group had a significant risk of BC (hazard ratio [HR]=2.289, 95% confidence interval [CI]=2.241-2.338) and RC (HR=2.199, 95% CI=2.061-2.348) than the 5ARI group. Among the 5ARIs group, though the incidence of BC was maintained (slope=-0.002 per year, p=0.79) after an initial increase for two years, the rate of RC decreased (slope=-1.1, p<0.001) consistently for ten years during the administration. CONCLUSIONS: Compared to the untreated group, 5ARIs use was associated with lower rates of BC and RC. In contrast to the increase in BC seen with short-term use of less than two years, long-term use of 5ARIs decreased the rate of RC in a duration-dependent manner for ten years, suggesting a strategy to prevent disease progression.

Comparison of adjuvant capecitabine plus oxaliplatin (CAPOX) versus S-1 after gastrectomy: a population-based cohort study using a nationwide claims database.

Although both capecitabine plus oxaliplatin (CAPOX) and S-1 are accepted as adjuvant chemotherapy following gastrectomy for gastric cancer, the better option between the two is still controversial. We conducted a retrospective nationwide cohort study using data from the National Health Insurance Service of Korea. We included patients who underwent gastrectomy for a primary diagnosis of gastric cancer between January 1, 2013, and December 31, 2018. The study compared the survival outcomes of patients who received postoperative chemotherapy based on S-1 (Arm S) vs. CAPOX (Arm C), as well as other relevant clinical variables such as comorbidity and completion of planned treatment. A total of 6602 patients were included in the analysis, with 4199 in Arm S and 2403 in Arm C. After propensity score matching, the final study population consisted of 2067 patients in each arm. Arm C showed statistically inferior 5-year overall survival (OS) and disease-free survival (DFS) rates compared to Arm S (84.0% vs. 90.0%; p < 0.0001; and 78.4% vs. 86.1%; p < 0.0001). Age (65 ≥ vs. < 65) and the incomplete planned treatment also had a significant negative effect on both OS and DFS. In the multivariable analysis, Arm C still showed worse OS (hazard ratio [HR], 1.609; 95% confidence intervals [CI], 1.339-1.934; p < 0.0001) and DFS (HR, 1.552; 95% CI 1.333-1.807; p < 0.0001) than Arm S. Both S-1 and CAPOX showed excellent efficacy, but this nationwide cohort study suggests that S-1 may be a better option in certain clinical situations.

Impact of guideline-directed medical therapy on 5-year mortality in patients with newly diagnosed peripheral artery disease.

OBJECTIVE: Current guidelines recommend that patients with peripheral artery disease (PAD) should be treated with antithrombotic agents, renin-angiotensin-system blockers, and statins. However, the clinical impact of guideline-directed medical therapy (GDMT) on long-term mortality in patients with newly diagnosed PAD remains unclear. We aimed to investigate the prevalence of GDMT and evaluate 5-year mortality according to GDMT after PAD diagnosis. METHODS: This retrospective cohort study, using nationwide health insurance claims data in Korea, included patients newly diagnosed with PAD between 2006 and 2015. GDMT was defined as the use of all drugs, including antithrombotic agents, renin-angiotensin-system blockers, and statins, within 3 months of PAD diagnosis. The primary endpoint was all-cause mortality. RESULTS: We investigated 19,561 newly diagnosed patients with PAD without proven cardiovascular disease. Among the study population, 4378 patients (22.4%) were categorized in the GDMT and 15,183 (77.6%) in the non-GDMT groups. During the 5-year follow-up, GDMT showed a lower incidence of all-cause mortality than that of non-GDMT (2.8% vs 4.8%; adjusted hazard ratio, 0.329; 95% confidence interval, 0.257-0.421; P < .001). Even in the propensity-matched population, GDMT showed a lower mortality rate than non-GDMT (hazard ratio, 0.283; 95% confidence interval, 0.217-0.370; P < .001). As the number of guideline-recommended drugs increased, the mortality rate decreased proportionately. CONCLUSIONS: After PAD diagnosis, GDMT was associated with a lower incidence of mortality regardless of proven cardiovascular disease. This retrospective analysis showed an insufficient prevalence of GDMT among patients with PAD in real-world practice.

Participation and Prognostic Impact of Cardiac Rehabilitation After Acute Coronary Syndrome: Big-Data Study of the Korean National Health Insurance Service.

BACKGROUND: To investigate the actual rate and quality of cardiac rehabilitation (CR) participation in South Korea and its short-term impact on clinical outcomes after acute coronary syndrome (ACS). METHODS: Data, including confirmed ACS diagnosis, socio-demographics, comorbidities, clinical outcomes, and CR claim codes, were collected from the Korean National Health Insurance Service claims database and compared between the CR and non-CR groups. RESULTS: Overall, 102,544 patients were included in the study, of which only 5.8% attended CR. Regarding testing, 83.6% of CR patients performed the cardiopulmonary exercise test, but follow-up testing was infrequently performed; in addition, 53.1% of them participated in an electrocardiogram monitoring exercise, but over half participated in only one session. After 1:1 propensity score matching, post-ACS cardiovascular events were significantly lower in the CR group than in the non-CR group. The cumulative 3-year hazard ratio for all-cause death was 0.612 (95% confidence interval [CI], 0.495-0.756), recurrent ACS was 0.92 (95% CI, 0.853-0.993), CR readmission was 0.817 (95% CI, 0.768-0.868), and major adverse cardiovascular events (MACE) was 0.827 (95% CI, 0.781-0.874) in the CR group. CR was associated with a significant dose-response effect on MACE, with a reduction in incidence from 0.854 to 0.711. CONCLUSION: The actual rate of CR participation in South Korea remains low, and participation quality was not outstanding despite National Health Insurance coverage. Nevertheless, the impact of CR on cardiovascular outcomes after ACS was significantly superior. Efforts to increase CR participation should be increased by establishing new CR facilities and strategies to resolve associated barriers.

10-year survival outcome after clinically suspected acute myocarditis in adults: A nationwide study in the pre-COVID-19 era.

BACKGROUND: Clinical courses of acute myocarditis are heterogeneous in populations and geographic regions. There is a dearth of long-term outcomes data for acute myocarditis prior to the coronavirus disease pandemic, particularly in the older and female population. This study aimed to provide the nationwide epidemiologic approximates of clinically suspected acute myocarditis across adults of all ages over the long term. METHODS: From the nationwide governmental health insurance database, a retrospective cohort comprised all patients aged 20-79 who were hospitalized for clinically suspected acute myocarditis without underlying cardiac diseases from 2006 to 2018. The complicated phenotype was defined as requiring hemodynamic or major organ support. Over 10 years, all-cause mortality and index event-driven excess mortality were evaluated according to young-adult (20-39 years), mid-life (40-59 years), and older-adult (60-79 years) age groups. RESULTS: Among 2,988 patients (51.0±16.9 years, 46.2% women), 362 (12.1%) were of complicated phenotype. Of these, 163 (45.0%) had died within 1 month. All-cause death at 30 days occurred in 40 (4.7%), 52 (4.8%), and 105 (10.0%) patients in the young-adult, mid-life, and older-adult groups, respectively. For 10 years of follow-up, all-cause death occurred in 762 (25.5%). Even in young adult patients with non-complicated phenotypes, excess mortality remained higher compared to the general population. CONCLUSION: In hospitalized patients with clinically suspected acute myocarditis, short-term mortality is high both in young and older adults, particularly those with comorbidities and severe clinical presentation. Furthermore, excess mortality remains high for at least 10 years after index hospitalization in young adults.

Cardiovascular and renal protective effects of non-vitamin K antagonist oral anticoagulants and warfarin in patients with atrial fibrillation.

AIM: Data on the use of non-vitamin K antagonist oral anticoagulants (NOACs) in relation to the risk of cardiovascular (CV) disease and renal protection among patients with atrial fibrillation (AF), are relatively sparse. We aimed to compare the effectiveness and safety of NOACs with those of warfarin for vascular protection in a large-scale, nationwide Asian population with AF. METHODS AND RESULTS: Patients with AF who were prescribed oral anticoagulants according to the Korean Health Insurance Review and Assessment database between 2014 and 2017 were analyzed. The warfarin and NOAC groups were balanced using propensity score weighting. Clinical outcomes included ischemic stroke, myocardial infarction, angina pectoris, peripheral artery disease, chronic kidney disease (CKD), end-stage renal disease (ESRD), CV death, and all-cause death. NOAC use was associated with a lower risk of angina pectoris (HR, 0.79 [95% CI, 0.69-0.89] p<0.001), CKD stage 4 (HR, 0.5 [95% CI, 0.28-0.89], p = 0.02), and ESRD (HR, 0.15[95% CI, 0.08-0.32], p<0.001) than warfarin use. NOACs and warfarin did not significantly differ with respect to stroke reduction (HR, 1.05 [95% CI, 0.88-1.25], p = 0.19). NOAC use was associated with a lower risk of intracranial hemorrhage (HR, 0.6 [95% CI, 0.44-0.83], p = 0.0019), CV death (HR, 0.55 [95% CI, 0.43-0.70], p<0.001), and all-cause death (HR, 0.6 [95% CI, 0.52-0.69], p<0.001) than warfarin use. CONCLUSION: NOACs were associated with a significantly lower risk of adverse CV and renovascular outcomes than warfarin in patients with AF.

Seasonality in hip fracture among haemodialysis patients and kidney transplant recipients in South Korea.

AIM: The seasonality of hip fracture in haemodialysis (HD) patients and kidney transplant recipients (KTRs) have not been reported. We assessed seasonal variations in hip fractures among patients with end-stage kidney disease who undergo maintenance HD and KTRs. METHODS: Using the Korean National Health Insurance System database from January 2012 to December 2017, monthly counts of hip fracture were calculated among HD patients (n = 77 420) and KTRs (n = 8921). The 6-year normalized monthly fraction and seasonal fractions of hip fractures were calculated. A cosinor analysis was performed to determine the seasonality of the monthly incidence of hip fractures. RESULTS: The 6-year average monthly fraction of hip fractures was lowest in June and highest in October in HD patients, and lowest in February and highest in November in KTRs. The 6-year average seasonal fraction among HD patients was lowest in summer and highest in winter, and lowest in summer and highest in autumn among KTRs, but there was no significant difference. The incidence ratio of hip fractures was lowest in June and highest in January in HD patients, and lowest in August and highest in November in KTRs. On cosinor analysis, HD patients showed significant seasonality in hip fracture incidence, with a trough in summer and a peak in winter (p = .031), whereas KTRs did not exhibit a significant trend (p = .44). CONCLUSION: Hip fractures occurred more frequently in winter and less frequently in summer in patients undergoing HD, whereas KTRs did not show a seasonal trend.

Severe hypoglycemia and risk of hospitalization for heart failure in adults with diabetes treated with oral medications with or without insulin: A population-based study.

AIMS: We aimed to determine if severe hypoglycemia (SH) independently increases the risk of hospitalization for heart failure (hHF) in type 2 diabetes, regardless of the prevalent or incident cardiovascular disease (CVD). METHODS: This was a nationwide population-based propensity score-matched study using Korean National Health Insurance Service data (2002-2018). The hazards of hHF were compared in individuals who experienced SH (n = 8,965) and 1:3 matched controls, among adults with diabetes using oral anti-diabetes medications (OADs) with or without insulin and without previous hHF at baseline. RESULTS: During 236,417 person-years, 1,189 cases of hHF occurred. The hazard of hHF was higher in individuals with SH compared to matched controls (adjusted hazard ratio [aHR] 1.503, 95 % confidence interval [CI] 1.324-1.707). The increase in aHR remained significant when excluding participants with prevalent or incident major adverse cardiovascular events (MACE; aHR 1.352, 95 % CI 1.228-1.622) and any CVD (aHR 1.342, 95 % CI 1.025-1.756). Two or more SH events were associated with further increase in hHF risk. CONCLUSION: SH was associated with increased risks of hHF among adults with diabetes using OAD with or without insulin. The increased risk was attenuated but remained significant in those without prevalent or incident MACE or CVDs.

Status of Glucocorticoid-Induced Osteoporosis Preventive Care in Korea: A Retrospective Cohort Study on the Korean National Health Insurance Service Database.

Background and Objectives: It is crucial to prevent osteoporosis in patients receiving long-term glucocorticoid (GC) treatment. This study aimed to investigate the frequency and associated factors of preventive care for glucocorticoid-induced osteoporosis (GIOP) in Korea. Materials and Methods: Using the Korean National Health Insurance Service database, we identified 37,133 individuals aged ≥ 20 years who commenced long-term (≥90 days) oral GC between 2011 and 2012. High-quality GIOP preventive care was defined as either a bone mineral density (BMD) test, calcium and/or vitamin D supplementation, or prescription osteoporosis medications within 6 months of GC initiation. Multivariable logistic regression models were used to calculate odds ratios (ORs) for associated factors for high-quality GIOP preventive care. Results: The mean age was 49.8 years, and 18,476 (49.8%) patients were female. The frequency of high-quality GIOP preventive care was only 3.68% (BMD test, 1.46%; osteoporosis medications, 1.65%; calcium/vitamin D, 1.63%). Increasing age (OR = 2.53, p < 0.001; 40-49 years, OR = 3.99, p < 0.001; 50-59 years, OR = 5.17, p < 0.001; 60-69 years, OR = 8.07, p < 0.001; ≥70 years, respectively), systemic autoimmune disease (OR = 3.08, p < 0.001), rural residence (OR = 1.19, p = 0.046), concomitant hyperthyroidism (OR = 1.58, p = 0.007), and malignancy (OR = 1.59, p < 0.001) were significantly associated with a higher likelihood of receiving high-quality GIOP preventive care. Male sex (OR = 0.26, p < 0.001) and GC prescription in primary care clinics and nursing hospitals (OR = 0.66, p < 0.001) were associated with a lower rate of high-quality GIOP preventive care. Conclusions: Most Korean patients treated with GC did not receive appropriate preventive care for GIOP in real-world practice. More efforts are needed by clinicians to prevent, screen, and treat GIOP.

Comparative Effects of Sodium-Glucose Cotransporter 2 Inhibitor and Thiazolidinedione Treatment on Risk of Stroke among Patients with Type 2 Diabetes Mellitus.

BACKGROUND: Although cardiovascular outcome trials using sodium-glucose cotransporter-2 inhibitors (SGLT-2i) showed a reduction in risk of 3-point major adverse cardiovascular events (MACE), they did not demonstrate beneficial effects on stroke risk. Additionally, meta-analysis showed SGLT-2i potentially had an adverse effect on stroke risk. Contrarily, pioglitazone, a type of thiazolidinedione (TZD), has been shown to reduce recurrent stroke risk. Thus, we aimed to compare the effect of SGLT-2i and TZD on the risk of stroke in type 2 diabetes mellitus (T2DM) patients. METHODS: Using the Korean National Health Insurance Service data, we compared a 1:1 propensity score-matched cohort of patients who used SGLT-2i or TZD from January 2014 to December 2018. The primary outcome was stroke. The secondary outcomes were myocardial infarction (MI), cardiovascular death, 3-point MACE, and heart failure (HF). RESULTS: After propensity-matching, each group included 56,794 patients. Baseline characteristics were well balanced. During the follow-up, 862 patients were newly hospitalized for stroke. The incidence rate of stroke was 4.11 and 4.22 per 1,000 person-years for the TZD and SGLT-2i groups respectively. The hazard ratio (HR) of stroke was 1.054 (95% confidence interval [CI], 0.904 to 1.229) in the SGLT-2i group compared to the TZD group. There was no difference in the risk of MI, cardiovascular death, 3-point MACE between groups. Hospitalization for HF was significantly decreased in SGLT-2i-treated patients (HR, 0.645; 95% CI, 0.466 to 0.893). Results were consistent regardless of prior cardiovascular disease. CONCLUSION: In this real-world data, the risk of stroke was comparable in T2DM patients treated with SGLT-2i or TZD.

Prevalence and Treatment of Vulvar Cancer From 2014-2018: A Nationwide Population-Based Study in Korea.

BACKGROUND: Vulvar cancer is one of the rare gynecologic malignancies. Despite the recent increasing trend of vulvar cancer in western countries due to the increased infection of human papillomavirus, there has been no study for population-based incidence of vulvar cancer in Korea. We aimed to investigate the prevalence and treatment of vulvar cancer in South Korea between 2014 and 2018. METHODS: Data from patients diagnosed and treated with vulvar cancer between 2014 and 2018 were obtained from the Health Insurance Review and Assessment Service/National Inpatient Sample (National In-Patient Sample) in South Korea. RESULTS: A total of 4,636,542 women were identified through the HIRA-NIS database from 2014 to 2018, of which 259 patients were diagnosed and treated for vulvar cancer. The mean age diagnosed with vulvar cancer was 62.82 (± 14.30) years in 2014, 64.19 (± 16.79) years in 2015, and 67.40 (± 14.41) years in 2016. In terms of treatment modalities, the most frequent treatment was surgery only without chemotherapy or radiation therapy. In the age-specific prevalence analysis, vulvar cancer was the most prevalent among those over 70 years old. According to multiple regression analysis, patients' age was significantly associated with the prevalence of vulvar cancer. Vulvar cancer was more prevalent in women with low socioeconomic status (SES) compared to those with high SES in 2018 (OR, 4.242; P < 0.001). CONCLUSION: Considering the high prevalence of vulvar cancer in the elderly, it is necessary to establish a new strategy for early screening and treatment.

Raman Scattering Study on the Influence of E-Beam Bombardment on Si Electron Lens.

Microcolumns have a stacked structure composed of an electron emitter, electron lens (source lens), einzel lens, and a deflector manufactured using a micro electro-mechanical system process. The electrons emitted from the tungsten field emitter mostly pass through the aperture holes. However, other electrons fail to pass through because of collisions around the aperture hole. We used Raman scattering measurements and X-ray photoelectron spectroscopy analyses to investigate the influence of electron beam bombardment on a Si electron lens irradiated by acceleration voltages of 0, 20, and 30 keV. We confirmed that the crystallinity was degraded, and carbon-related contamination was detected at the surface and edge of the aperture hole of the Si electron lens after electron bombardment for 24 h. Carbon-related contamination on the surface of the Si electron lens was verified by analyzing the Raman spectra of the carbon-deposited Si substrate using DC sputtering and a carbon rod sample. We report the crystallinity and the origin of the carbon-related contamination of electron Si lenses after electron beam bombardment by non-destructive Raman scattering and XPS analysis methods.

Nationwide population-based study of prevalence and trend of borderline ovarian tumors in the Republic of Korea.

Borderline ovarian tumors (BOTs) represent noninvasive tumors with uncertain malignant potential. They have a favorable prognosis although they can also recur or be fatal. There are limited population-based data on BOTs, its incidence and surgical treatment approach. We sought to analyze these trends in South Korea between 2014 and 2018. Data from patients diagnosed with BOT between 2014 and 2018 were obtained from the Health Insurance Review and Assessment Service/National Inpatient Sample in South Korea. Treatment was analyzed by using codes including adnexal surgery with or without hysterectomy. Data from 4,636,542 women were entered into the database between 2014 and 2018. Data from 5,109 women with BOT, and 537 women with surgery were extracted for analysis. The highest prevalence of BOT occurred in women 40-44 years old. In logistic regression analysis, age was significantly correlated with the prevalence of BOT (p < 0.05). The prevalence of BOT was lower in individuals over 50 than it was in those under 50 years (odds ratio (OR), 0.400 in 2014; OR, 0.457 in 2015; OR, 0.419 in 2016; OR, 0.355 in 2017; OR, 0.347 in 2018). The prevalence of BOT varies significantly with age, and is most common in women in their 40 s.

Process Development for the Detoxification of Fermentation Inhibitors from Acid Pretreated Microalgae Hydrolysate.

The aim of this study was to remove 5-hydroxymethyl furfural (5-HMF) and furfural, known as fermentation inhibitors, in acid pretreated hydrolysates (APH) obtained from Scenedesmus obliquus using activated carbon. Microwave-assisted pretreatment was used to produce APH containing glucose, xylose, and fermentation inhibitors (5-HMF, furfural). The response surface methodology was applied to optimize key detoxification variables such as temperature (16.5-58.5 °C), time (0.5-5.5 h), and solid-liquid (S-L) ratio of activated carbon (0.6-7.4 w/v%). Three variables showed significant effects on the removal of fermentation inhibitors. The optimum detoxification conditions with the maximum removal of fermentation inhibitors and the minimum loss of sugars (glucose and xylose) were as follows: temperature of 36.6 °C, extraction time of 3.86 h, and S-L ratio of 3.3 w/v%. Under these conditions, removal of 5-HMF, furfural, and sugars were 71.6, 83.1, and 2.44%, respectively, which agreed closely with the predicted values. When the APH and detoxified APH were used for ethanol fermentation by S. cerevisiae, the ethanol produced was 38.5% and 84.5% of the theoretical yields, respectively, which confirmed that detoxification using activated carbon was effective in removing fermentation inhibitors and increasing fermentation yield without significant removal of fermentable sugars.